Quick hitch attachment

ABSTRACT

An attachment for a prime mover or backhoe which may be used to cut or crush material. The attachment includes a first jaw, being a fixed jaw, and a second jaw being a free jaw which is pivotably connected to the fixed jaw, and at least three connectors which allow the attachment to be connected to the actuator arm of a prime mover or backhoe. These connectors include a head connector adapted to provide a connection to the head of the actuator arm, and a driven connector adapted to provide a connection to the driving beam of the backhoes actuator arm, and a strut connector adapted to provide a connection to the strut of the backhoes actuator. The head and driven connectors are associated with the fixed jaw and the strut connector is associated with the free jaw, where the head and driven connectors are connected to the prime mover or backhoe with a quickhitch. The arrangement is such that when in use the distance between the driven and head connectors remains constant and the distance between the driven and strut or head and strut connectors varies.

TECHNICAL FIELD

This invention relates to devices used to cut and pulverise materials.Specifically the present invention may be used in the demolition tradeto provide a jaw attachment for an excavator and may be configured to beeasily and quickly removed from or attached to an excavator. The presentinvention may also be adapted to engage with a quickhitch locatedbetween elements of the excavator and the jaw, where the inclusion of aquickhitch improves the efficiency and the cutting or cutting strengthof the attachment.

Reference throughout this specification will also be made to the presentinvention being configured to provide a cutting or pulverising jawattachment for an excavator used in demolition work. However, it shouldbe appreciated by those skilled in the art that other applications areenvisioned for the present invention and reference to the above onlythroughout this specification should in no way be seen as limiting.

BACKGROUND ART

A number of cutting, crushing or manipulating jaws have previously beendeveloped which attach to an excavator or other similar heavy machinery.These attachment jaws can be used in the demolition industry to cut upmetal structures or crush concrete structures.

Such attachments are connected to the free end of an excavator'sactuator arm. The free end of such an arm includes a main head portion,a support strut adjacent to the head portion (and attached to the armfurther back from the head) and lastly an actuator beam adjacent thehead portion which may move towards and away on the head portion toactuate or operate attachments connected to the excavator.

One relatively effective form of attachment jaw developed for anexcavator is produced by Pemberton Incorporated of Longwood, Orlando,Fla., United States of America. This attachment may be termed a‘self-driven’ jaw as it relies only on the actuator beam of theexcavator to open and close the jaw when the device is in use. This maybe contrasted with other known types of attachment jaws that employtheir own self-contained hydraulic or pneumatic rams to drive portionsof the jaws. Therefore these devices also require connections to sourcesof hydraulic fluid or pressurised gas that increases maintenance costsand increases the time required to connect an attachment to anexcavator.

Therefore Pemberton self-driven attachment is relatively simple toproduce and easy to use when compared to other types of attachment jaw.However, one existing problem with this and similar devices is theamount of time it takes to either connect or disconnect the attachmentfrom the excavator's actuator arm. A number of bolts or locking pins areused to connect points on the jaws to the head, strut and actuator beamof the excavator arm. The separate connection of each of these points tothe attachment jaws and the weight of the attachment jaws themselvessignificantly complicate the connection or disconnection of theattachment to the excavator.

A device known as a quick hitch has also previously been developed in anattempt to speed up and simplify the connection of attachments toexcavators. An example of a quick hitch is given in U.S. Pat. No.5,082,389 to Balemi. This type of device is normally connected to thehead and beam ends of an excavator's actuator arm and allows anattachment's connector pins or bolts to be quickly connected to thequick hitch and hence the associated beam and head of the actuator arm.The use of a quick hitch means that only the actuator arm's strut needsto be manhandled and attached separately to the excavator.

It is also preferably for the attachment jaws discussed above to applythe greatest force or pressure possible when the jaws are closed aroundan object to be cut or crushed. By having strong forces applied when thejaws are closed this substantially speeds up the operation of theexcavator and also allows the jaws to cut or crush relatively dense orstrong material.

A self-driven shearing pulverising device that solved any or all of theif above problems would be of great advantage relative to the prior art.Specifically a self-driven shearing or pulverising device which couldapply high forces to any objects contained within its jaws, and whichcould be connected to an excavator's actuator arm using a quick hitch orother similar device would be advantageous.

It is an object of the present invention to address the foregoingproblems or at least to provide the public with a useful choice.

Further aspects and advantages of the present invention will becomeapparent from the ensuing description that is given by way of exampleonly.

DISCLOSURE OF INVENTION

According to one aspect of the present invention there is provided anattachment for a prime mover, wherein the attachment includes:

(a) a first jaw being a fixed jaw, and a second jaw, said second jawbeing a free jaw which is pivotably connected to the fixed jaw, and

(b) at least three connectors which allow the attachment to be connectedto the actuator arm of a prime mover, wherein said connectors include:

(i) a head connector adapted to provide a connection to the head of theprime mover's actuator arm, and

(ii) a driven connector adapted to provide a connection to the drivingbeam of the prime mover's actuator arm, and

(iii) a strut connector adapted to provide a connection to the strut ofthe prime mover's actuator arm,

wherein the head and driven connectors are associated with the fixedjaw, and the strut connector is associated with the free jaw, the headand driver connectors being connected to the prime mover with aquickhitch,

the arrangement and construction being such that when in use thedistance between the driven and head connectors remains constant and thedistance between the driven and strut or head and strut connectorsvaries.

According to a further aspect of the present invention there is providedan attachment substantially as described above which includes aquickhitch attached to the head and driven connectors associated withthe fixed jaw, said quickhitch being adapted for connection to the headand driving beam of the prime mover's actuator's arm.

An attachment formed in accordance with the present invention may be anytype of apparatus or arrangement of elements which is adapted to connectto actuator arm, boom or any piece of machinery that can operate theattachment. Preferably such attachments may be configured to cut, crush,crack, shear, dig, collect, or break up a number of different types ofmaterials. For example in some embodiments the present invention may beused in the demolition industry to provide an attachment which canperform some of the above functions on a demolition site.

Preferably the prime mover which the attachment is adapted to connect tomay be an excavator or any other similar type of heavy machinery. Thesetypes of machine are well known in the demolition and constructiontrades and as such will not be described in detail throughout thisspecification. Those skilled in the art should appreciate that referenceto a prime mover may encompass any type of machine which can be adaptedto move or operate an attachment configured in accordance with thepresent invention.

Reference throughout this specification will also be made to theattachment being connected or attached to the actuator arm of anexcavator. An excavator may be any type of apparatus known in the artwhich includes such an actuator arm and which can be used to drive oroperate an attachment configured in accordance with the presentinvention. Further, an excavator used in conjunction with the presentinvention may include an actuator arm with a head, strut and drivenbeam-ends on the free end of the actuator arm or boom.

In a preferred embodiment the excavator arm driven beam may beconfigured as a hydraulic ram where the hydraulic fluid that operatesthe ram is supplied from the excavator. This configuration of theinvention ensures that a hydraulic ram configured as a driven beam inthe excavator can be used to operate the present invention.

In a preferred embodiment the present invention may include at least twojaws. The first of these jaws that may be defined as the fixed jaw maybe pivotally connected to a second jaw defined as a free jaw. In use atleast these two jaws can move towards and away from each other to cut orshear different types of material. Those skilled in the art should alsoappreciate that other functions are envisioned for the jaws used for thepresent invention and reference to cutting or shearing material onlythroughout this specification should in no way be seen as limiting.

Reference throughout this specification shall now also be made to theattachment including two jaws only. Again, it should be appreciated bythose skilled in the art that any number and type of jaws may be used inconjunction with the present invention if required.

In a preferred embodiment the attachment may include a number ofconnectors which allow the attachment to be connected to the actuatorarm of an excavator. These attachments are provided to ensure that theexcavator can move and operate the attachment effectively.

In a preferred embodiment the attachment may be indirectly connected toan actuator arm through its connectors being connected to a quick hitchwhich is in turn connected to the head and ram ends of an actuator arm.As discussed previously, an example of a quick hitch is provided in U.S.Pat. No. 5,082,389. This document shows in FIG. 1 two apertures 8,9 thatcan be connected to the head and ram ends of an actuator arm with a pairof locking pins. Such a device may be used to provide an indirectconnection between the excavator arm and the invention using a number ofconnectors.

Reference throughout this specification will now be made to theattachment being connected to an excavator through a quick hitch. Thoseskilled in the art should appreciate that any type of quickhitch may beused in conjunction with the present invention which need notnecessarily employ the quickhitch design described in U.S. Pat. No.5,082,389.

In a preferred embodiment the present invention may include threeconnectors only, where these three connectors may be defined as the headconnector, the driven connector and the strut connector.

In a preferred embodiment the attachment jaws may be configured so thatthe driven connector and head connector are associated with the first orfixed jaw. In such an embodiment the strut connector may also beassociated with the second or free jaw.

In a preferred embodiment the first fixed jaw may include or have formedwithin it a pair of connector pins to create the head and drivenconnectors. The two pins used as connectors may be permanently welded orattached to the main body of the fixed jaw and will allow the fixed jawto be quickly attached to a quick hitch.

In some embodiments the strut connector may be configured as a pinslotting into a hollow space within one end of the second or free jaw.The strut connector pin may be removable attached to the free jaw sothat the excavator arm strut may be directly connected to the free jawthrough the pin being positioned or slotted between both components.

However, in a preferred embodiment the strut connector need notnecessarily include a moveable pin that can slot into a space within oneend of the second or free jaw. Preferably a strut may be permanently andpivotably attached to the second or free jaw with the opposite free endof the strut extending up to engage with an attachment system located onthe excavator arm.

In such an embodiment the free end of the strut may include a bifurcatedend assembly with apertures in each bifurcation provided. A single pinmay be slotted through each of these apertures where this pin may begrasped and retained by the attachment system used.

The attachment system may also include a housing with a single open faceor wall within which the pin located on the end of the strut may beinserted. To retain the strut end's pin and therefore the strut inplace, the attachment system may also include a moveable end wall thatcan be fixed in place over the open end or face of the attachment systemhousing.

In a further preferred embodiment the moveable end wall of theattachment system may be formed by a hook assembly pivotably attached tothe body of the attachment system used to form the open ended housing.The hook used may be arranged so as to pivot into place to cover theopen end or face of the attachment system housing and therefore lock inplace the pin at the end of the strut when located within the attachmentsystem housing.

This configuration of the invention allows a quick hitch to be used toindirectly connect the fixed jaw of the attachment to the head and ramof the excavator arm. When the attachment is in use the distance betweenthe head connector and driven connector must stay constant as these twoconnectors are permanently fixed to or integrally formed from the fixedjaw. However, when the fixed and free jaws are brought together thedistance between the strut connector and the head or driven connectorsvaries as the jaws pivot and the strut connector pin rotates to allowthe free jaw to move.

Furthermore, the use of an attachment system substantially as discussedabove allows a strut permanently attached to the free jaw to be quicklylocated and locked in place on the excavator. The excavator's operatorsimply needs to actuate and move the excavator's ram to slide the freeend of the strut in place within the attachment system to lock same inplace.

The attachment jaws of the present invention may simply be operated bythe excavator operator activating the actuator arm hydraulic ram.Operation of the ram will cause the end of the fixed jaw to pivottowards the free jaw.

The combination of the above set of attachment jaws with a quickhitchinterposed between the excavator actuator arm and the head and drivenconnectors provides a substantial increase in the forces applied toclose the attachment jaws. The addition of a quickhitch placesadditional distance between the main pivoting connection of the free andfixed jaws and the actuator arm used to apply a closing force to thejaws. This additional distance substantially increases the leverage thatcan be applied by the excavator arm to close the quickhitch jaws.

In addition, the use of a quickhitch between the jaws and the excavatorplaces an additional distance between the head connector and the mainpivot of the jaws. This will in some embodiments result in theapplication of an additional significant levering force applied to closethe jaws of the attachment. This may be contrasted with an attachmentwhich does not use a quickhitch and which will provide the headconnection in close proximity to the main pivot point of the jaws,eliminating the possibility of an additional significant levering forcebeing applied to the jaws.

Furthermore, in some instances the strut connector used may also bepositioned on an extended leg or projection formed in the free jaw,which will again increase the distance between the strut connector andthe main pivoting connection between the two jaws. Increasing thedistance between the point at which the force is applied to the jaws andthe main pivotable connection between the jaws will substantiallyincrease the leverage applied to close the jaws.

The present invention provides many potential advantages over existingprior art devices.

The present invention may be used to provide a self-driven excavatorattachment that requires no additional sources of pressurised air orfluid to be driven or operated. In such an embodiment the attachment maybe operated simply by the use of the hydraulic ram already incorporatedinto an excavator's actuator arm.

The present invention may also be specifically adapted to connect to anexcavator arm using a quick hitch. The use of a quick hitchsubstantially decreases the amount of time required to connect ordisconnect an attachment from the excavator arm.

Furthermore, the attachment system used to connect the end of a strut toan excavator arm also substantially speeds up the connection of theattachment to an excavator. The excavator's operator simply needs tomaneuver the free end of the strut permanently connected to theattachment into contact with the attachment system's housing tofacilitate the connection of the strut to the excavator arm.

The arrangement and configuration of the attachment discussed aboveallows it to be combined with quickhitch attachment systems. Themechanical arrangement of the pivot points, levering arms and jawsinvolved substantially increases the forces applied to close the jawswhen a quickhitch is present. As the pivot points for the head anddriven connector are further displaced away from the main pivot of thejaws, this substantially increases the levering force applied throughthese connectors onto any object to be crushed, cut or grasped by thejaws. Through the addition of a quickhitch the attachment may workquickly to cut through dense and strong materials which could causedifficulties to other forms of attachment with lower forces applied toclose the attachment jaws.

BRIEF DESCRIPTION OF DRAWINGS

Further aspects of the present invention will become apparent from theensuing description that is given by way of example only and withreference to the accompanying drawings in which:

FIG. 1 shows an attachment as configured in one embodiment indirectlyconnected to an excavator via a quick hitch, where the attachment jawsare open; and

FIG. 2 shows the same attachment, quick hitch, and excavator arm asshown in FIG. 1 but with the attachment jaws closed.

FIGS. 3 to 5 show an attachment system used to attach a strutpermanently connected to the attachment to the excavator arm.

FIGS. 6 and 7 show a force analysis completed on the open jaws of anattachment provided without a quickhitch, and an attachment providedwith a quickhitch.

MODES FOR CARRYING OUT THE INVENTION

FIG. 1 shows an attachment 1 for an actuator arm 2 of an excavator (notfully shown).

The attachment 1 is indirectly connected to the actuator arm 2 through aquick hitch 3. The quick hitch 3 is directly connected to the actuatorarm driven beam 4 and also to the actuator arm head 5. The driven beam 4is connected to a hydraulic ram (not shown) that is powered or driven bythe excavator. In the situation shown in FIG. 1 the excavator ram isretracted. This means that there is no requirement for hydraulic orpneumatic lines to be fitted to the attachment 1 as it may be operatedusing the excavator's own hydraulic ram and driven beam 4.

The attachment 1 as configured in the embodiment shown is a pair of jawscomprising a first or fixed jaw 6 and a second or free jaw 7. The fixedjaw 6 is pivotally connected to the free jaw 7 by a pivot point 8. Thetop end 7 a of the free jaw is directly connected to the actuator armstrut 9. This strut is connected at its opposite end to the head portion5 of the arm further away from the attachment.

The fixed jaw 7 includes a removable strut connector pin 10 that ispassed through both the end 7 a of the free jaw and the end of the strut9.

The fixed jaw 6 incorporates two connectors being a head connector 11and a driven connector 12. In the embodiment shown these connectors areformed from pins which are integral parts of the fixed jaw. These headand driven connectors are permanently fixed in place and need not beremoved for the invention to function properly or for the attachment tobe removed from or be attached to an excavator. The head and beamconnectors can be used to easily and quickly connect the attachment tothe quick hitch 3.

FIG. 2 shows the same apparatus as FIG. 1 but this time where thehydraulic ram of the driven beam 4 has been extended. In this instancethe extension of the excavator's ram will cause the bottom end 6 a ofthe fixed jaw to move round the pivot towards the opposite face of thefree jaw 7. At the same time the strut connector pin 10 will move bothrelative to the head connector 11 and driven connector as the jaws pivotclosed.

Even when the excavator's ram is extended the distance between both thefixed jaw head connector 11 and driven connector 12 remain constant,thereby keeping the fixed jaw 6 solidly in contact with the quick hitch3 and hence the actuator arm 2.

FIGS. 3, 4 and 5 show the steps involved with connecting the end of astrut to an attachment system located on an excavator arm. In theembodiment shown in these figures, one end of the strut may bepermanently and pivotably connected to the free end of the attachmentjaw, while the attachment system shown can be used to connect the freeor opposite end of the strut to the excavator arm.

In the views shown, FIGS. 3a, 4 a and 5 a show side cross sectionalviews of the strut end and attachment system, whereas FIGS. 3b, 4 b and5 b show simple non cross section side views of the same components.

FIGS. 3a, 3 b show a situation where the free end of a strut 20 isdetached from an excavator 21 and is to be connected to the excavatorarm through use of an attachment system 22. The end of the strut has abifurcated assembly (not fully shown) with a set of apertures within thebifurcations that are adapted to receive a pin 23.

The attachment system 22 includes a main body portion which definesthree walls of a housing 24 which can be used to at least partiallyenclose the pin 23 located on the end of the strut 20. The attachmentsystem 22 also includes a hook assembly 25 that is pivotably attached atpoint 26 to the main body of the attachment system.

FIGS. 4a, 4 b show the situation where the excavator's operatormaneuvers the excavator arm to place the end of the strut 20 intocontact with the attachment system 22. As shown in these figures the pin23 of the strut 20 is maneuvered to locate the pin within the housing 24of the attachment system.

FIGS. 5a, 5 b show the last step in the attachment process. Once the pin23 has been located within the attachment system housing 24, the hookassembly 25 is pivoted towards the pin 23 so as to close off the openface or end of the housing 24 and therefore lock the pin and associatedstrut onto the excavator arm 21.

FIG. 6 shows a force analysis completed on the open jaws of anattachment which is provided without a quickhitch, whereas FIG. 7 showsa force analysis completed on the open jaws of an attachment which isprovided with a quickhitch.

In both the situations shown the forces present on the driven connector(A) head connector (B) and strut connector (C) are analysed and combinedtogether to give the total closing force applied to the jaws about themain pivot point (D) connecting the free and fixed jaws together.

As can be seen from FIG. 6 the total forces applied to close the jawsabout the pivot point (D) result from the addition of three separateforces to provide an overall effective force of 38 kN for the embodimentshown.

Conversely, FIG. 7 shows the situation where the same jaws used in FIG.6 have a quickhitch interposed between the head and driven connectorsand the excavator actuator arm. In this instance, the resultant closingforce present about pivotable point (D) is created by four forcescombining together to give an overall effective closing force of 65 kN.

As can be appreciated by those skilled in the art the additionaldistance between the main jaw pivot point (D) and the driven and headconnectors (A and B) provide significantly more leverage and anadditional force to the jaws when closed.

Aspects of the present invention have been described by way of exampleonly and it should be appreciated that modifications and additions maybe made thereto without departing from the scope thereof as defined inthe appended claims.

I claim:
 1. An attachment for a prime mover, the attachment including,(a) a first jaw being a fixed jaw, and a second jaw, said second jawbeing a free jaw which is pivotably connected to the fixed jaw, and (b)at least three connectors which allow the attachment to be connected toan actuator arm of the prime mover, wherein said connectors include, (i)a head connector incorporating a fixed pin adapted to provide aconnection to a head of the prime mover's actuator arm, and (ii) adriven connector incorporating a fixed pin adapted to provide aconnection to a driven beam of the prime mover's actuator arm, saiddriven beam being used to open and close the first and second jaws, and(iii) a strut connector adapted to provide a connection to a strut ofthe prime mover's actuator arm, wherein the head and driven connectorsare associated with the fixed jaw, and the strut connector is associatedwith the free jaw, the head and the driven connectors being connected tothe prime mover's actuator arm with a quickhitch, the arrangement andconstruction of the attachment being such when in use the distancebetween the driven and head connectors remains constant and the distancebetween the driven and strut or head and strut connectors varies.
 2. Anattachment as claimed in claim 1 which includes a quickhitch attached tothe head and driven connectors associated with the fixed jaw, saidquickhitch being adapted to form a connection to the head and drivingbeam of the prime mover's actuator arm.
 3. An attachment as claimed inclaim 1 wherein the prime mover is an excavator.
 4. An attachment asclaimed in claim 1 wherein the driven beam of the prime mover's actuatorarm is configured for connection to a hydraulic ram supplied withhydraulic fluid by the prime mover.
 5. An attachment as claimed in claim1 wherein the head and driven connectors are formed from pinspermanently attached to the fixed jaw.
 6. An attachment as claimed inclaim 1 wherein the strut connector is formed through a moveable pinslotted into a hollow space within the free jaw.
 7. An attachment asclaimed in claim 1 wherein the prime mover strut is permanentlyconnected to the free jaw and a free end of the strut is adapted toengage with an attachment system associated with the prime mover'sactuator arm.
 8. An attachment as claimed in claim 7 wherein the freeend of the strut includes a bifurcated end assembly with aperturesprovided in each bifurcation.
 9. An attachment as claimed in claim 7wherein the attachment system which the free end of the strut is adaptedto engage with includes a housing with a single open face configured toreceive a pin provided in the free end of the strut.
 10. An attachmentas claimed in claim 9 wherein the attachment system includes a moveableend wall adapted to move over the open face of the attachment systemhousing.
 11. An attachment as claimed in claim 10 wherein the moveableend wall is formed from a pivotable hook assembly.
 12. An attachment asclaimed in claim 8 wherein the attachment system which the free end ofthe strut is adapted to engage with includes a housing with a singleopen face configured to receive a pin provided in the free end of thestrut.